package com.zlq.lambda.java;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Consumer;
import java.util.function.Predicate;



/*
 * java内置的4大核心函数式接口
 *
 * 消费型接口 Consumer<T>     void accept(T t)
 * 供给型接口 Supplier<T>     T get()
 * 函数型接口 Function<T,R>   R apply(T t)
 * 断定型接口 Predicate<T>    boolean test(T t)
 *
 */

public class LambdaTest2 {
    @Test
    public void test1(){
        happyTime(500, new Consumer<Double>() {
            @Override
            public void accept(Double aDouble) {
                System.out.println("学习很累，去消费花费"+aDouble);
            }
        });
        System.out.println("*******************");
        happyTime(400,money -> System.out.println("学习很累，去消费花费"+money));

    }
    public void happyTime(double money, Consumer<Double> con){
        con.accept(money);
    }

    @Test
    public void test2(){
        List<String> list = Arrays.asList("北京","南京","天津","上海","郑州");
        List<String> filterStr = filterString(list, new Predicate<String>() {
            @Override
            public boolean test(String s) {
                return s.contains("京");
            }
        });
        System.out.println(filterStr);

        List<String> filterStr2 = filterString(list,s -> s.contains("京"));
        System.out.println(filterStr2);

    }
    //根据给定的规则，过滤集合中的字符串，此规则由Predicate的方法决定
    public List<String> filterString(List<String> list, Predicate<String> pre){
        ArrayList<String> filterList = new ArrayList<>();

        for (String s : list){
            if (pre.test(s)){
                filterList.add(s);
            }
        }
        return filterList;
    }

}
